Cyclic adenosine monophosphate is a kind of vital substance with physiological activity, which wildly exists in human body and functions as an intracellular second messenger to play an important role in the synthesis and regulation of carbohydrates, fat metabolism, nucleic acids, proteins and the like. It is used for treating angina pectoris, myocardial infarction, myocarditis, and cardiogenic shock in clinic, has effects on ameliorating symptoms of rheumatic heart disease, such as palpitation, dyspnea, chest distress and the like. It can enhance therapeutic effects of combined chemotherapy on acute leukemia and also can be applied in induced remission of acute leukemia. In addition, it has some therapeutic effects on senile chronic bronchitis, various hepatitis and psoriasis too. Cyclic adenosine monophosphate can also be used to prepare dibutyryl adenosine cyclophosphate and meglumine adenosine cyclophosphate as drug intermediate to increase their solubility in lipid so that they may exert their physiological and pharmacological functions more effectively. Cyclic adenosine monophosphate can be used as food additives for poultry and livestock too where it can simulate roles of growth hormones in vitro to promote growth of poultry and livestock and increase yield of high-quality poultry products.
There are three main methods for preparing cyclic adenosine monophosphate, which are chemical synthesis, fermentation and enzymatic conversion. Currently, all cyclic adenosine monophosphate is prepared by chemical synthesis in foreign and domestic, which uses adenosine monophosphate as starting material, utilizes high performance separation column to separate intermediates, but has complicated operations, huge consumption of solvents, low recovery rate, high cost, and low yield. Fermentation is to incubate microbe cells in minimal medium containing C and N sources with addition of precursor and thereby prepare a large amount of cyclic adenosine monophosphate. But this method has some technical bottlenecks, such as cell membrane permeability, mass transfer of oxygen, environmental coadaptation mechanism and the like, so there is still some distance away from industrialization. Whole-cell biocatalysis is to utilize cyclic adenosine monophosphate synthetase system derived from mammals or microbes (arthrobacter, Brevibacterium liquefaciens and the like) to synthesize cyclic adenosine monophosphate. Since cells have the entire multienzyme system for maintaining vital activities and various enzymes retain the original state and particular location in living cells, utilizing microbial cells directly as enzyme source to conduct enzymic catalytic reaction enable multistep enzymic catalytic reaction to be completed rapidly and efficiently and may also cause the step of extracting enzymes from microbial cells to be skipped. This method is attracting more and more researchers' attention due to the features such as high purity of reaction products, simple isolation and purification procedure, short reaction period, pollution-free and the like.